Conventionally, there is a device for performing wireless communication at a short distance. For example, in communication based on the Bluetooth (registered trademark) standard, a certain device as a master and another device as a slave form a single network and communicate with each other.
In the conventional wireless communication, however, there is room for improvement in the communication of a device in the state of being connected to a certain device, with various devices.
Therefore, it is an object of an exemplary embodiment to provide a technique for communicating with various devices.
To achieve the above object, the exemplary embodiment employs the following configurations.
An example of the exemplary embodiment is a wireless system including a plurality of devices capable of performing wireless communication, the wireless system including a first device, a second device, a third device, and a fourth device. The first device and the second device establish a connection between the first device and the second device such that the first device is a master and the second device is a slave, and performing wireless communication with each other. The fourth device and the third device establish a connection between the fourth device and the third device such that the fourth device is a master and the third device is a slave, and performing wireless communication with each other. The second device in the state of being connected as a slave to the first device performs wireless communication with the third device in the state of being connected as a slave to the fourth device.
Based on the above, a second device operating as a slave of a first device can communicate with a third device operating as a slave of a fourth device.
Here, “establishing a connection” means that after information is exchanged by a device transmitting information necessary for a connection to another device, the devices enter the state of being connected (a connection state). In the state of being connected, the two devices communicate with each other based on information exchanged while the connection is established.
In an exemplary embodiment, the second device may execute a transmission process for wirelessly transmitting data by broadcast or multicast, and may execute a reception process for wirelessly receiving data transmitted by broadcast or multicast. The second device in the state of being connected as a slave to the first device executes the transmission process and the reception process, thereby communicating with the third device in the state of being connected as a slave to the fourth device.
Based on the above, the second device operating as a slave of the first device transmits and receives data by broadcast, and thereby can communicate with the third device operating as a slave of the fourth device.
Here, “broadcast” includes broadcast to unspecified devices (all devices in the range where communication can be performed) and broadcast to limited unspecified devices. A “limited unspecified device” is a device that is not uniquely specified (a unique address assigned to the device is not specified), but has a common attribute or is in a common state.
In an exemplary embodiment, the second device in a state of not being connected to the third device may transmit or receive predetermined data by wireless communication to or from the third device in the state of being connected as a slave to the fourth device.
Based on the above, the second device can communicate with the third device operating as a slave of the fourth device, without connecting to the third device.
In an exemplary embodiment, the second device may transmit or receive, as the predetermined data, data for use in an application.
In an exemplary embodiment, the second device may transmit or receive, as the predetermined data, data for use in a game.
In an exemplary embodiment, the second device may transmit or receive, as the predetermined data, data regarding a content reproduced in an application.
Based on the above, the second device and the third device can exchange data for use in an application (including a game) and data regarding a content to be reproduced in an application (for example, an image, a sound, and the like). That is, the second device connected as a slave to the first device can transmit and/or receive the above data to and/or from the third device connected as a slave to the fourth device.
In an exemplary embodiment, the second device in the state of being connected to the first device may repeatedly execute the transmission process and the reception process, thereby performing wireless communication with the third device in the state of being connected as a slave to the fourth device, without establishing a connection with the third device.
Based on the above, the second device can communicate with the third device without establishing a connection with the third device.
In an exemplary embodiment, the data to be transmitted by broadcast or multicast may be data for establishing a connection with another device.
Based on the above, broadcast or multicast data is transmitted, whereby it is possible to establish a connection with another device.
In an exemplary embodiment, the second device in the state of being connected as a slave to the first device may establish a connection with the third device in the state of being connected as a slave to the fourth device and may perform wireless communication with the third device in a state where the established connection is maintained.
Based on the above, the second device in the state of being connected as a slave to the first device can establish a connection with the third device in the state of being connected as a slave to the fourth device and communicate with the third device.
In an exemplary embodiment, the second device in the state of being connected as a slave to the first device may establish a connection with the third device in the state of being connected as a slave to the fourth device and may perform wireless communication with the third device without terminating the established connection.
Based on the above, the second device in the state of being connected as a slave to the first device can establish a connection with the third device in the state of being connected as a slave to the fourth device and communicate with the third device.
In an exemplary embodiment, the second device in the state of being connected to the first device may repeatedly execute the transmission process and the reception process, thereby performing wireless communication with another device present around the second device.
Based on the above, the second device in the state of being connected to the first device repeatedly performs a transmission process and a reception process by broadcast, and thereby can communicate with another device present around the second device.
In an exemplary embodiment, the second device may repeatedly execute the transmission process and the reception process to search for another device around the second device and may establish a connection with the third device detected by the search and in the state of being connected as a slave to the fourth device.
Based on the above, the second device in the state of being connected to the first device repeatedly performs the transmission process and the reception process by broadcast to search for the third device, and thereby can establish a connection with the third device in the state of being connected as a slave to the fourth device.
In an exemplary embodiment, at least any of an execution period of the transmission process, timing for executing the transmission process, an execution period of the reception process, and timing for executing the reception process may be variable.
In an exemplary embodiment, at least any of the execution period of the transmission process, the timing for executing the transmission process, the execution period of the reception process, and the timing for executing the reception process may be randomly set.
Based on the above, a transmission process and a reception process are repeatedly performed, whereby it is possible to, for example, match transmission timing of one device and reception timing of the other device.
In an exemplary embodiment, the second device may alternately and repeatedly execute the transmission process and the reception process. In the case where “the transmission process and the reception process are alternately and repeatedly executed”, the transmission process and the reception process may be alternately performed with a stopping period provided between the transmission process and the reception process.
Based on the above, for example, it is possible to shorten the time from transmission timing of one device to reception timing of the other device.
In an exemplary embodiment, a sleep period in which neither the transmission process nor the reception process is performed may be present at least between the transmission process and the reception process, between the transmission process and the transmission process, or between the reception process and the reception process.
Based on the above, a sleep period is provided in which neither the transmission process nor the reception process is performed. Thus, it is possible to reduce power consumption.
In an exemplary embodiment, the sleep period may be variable.
In an exemplary embodiment, the sleep period may be randomly set.
Based on the above, the transmission process and the reception process are repeatedly performed, whereby it is possible to, for example, match transmission timing of one device and reception timing of the other device.
In an exemplary embodiment, the second device may perform wireless communication with the third device in the state of being connected as a slave to the fourth device, without an instruction from the first device.
Based on the above, the second device can communicate with the third device without an instruction from the first device.
In an exemplary embodiment, in the state where the first device and the second device are connected together, the first device and the second device may repeatedly perform synchronous communication with each other.
Based on the above, the first device and the second device in the state of being connected together communicate with each other in synchronization with each other. That is, the transmitting end and the receiving end match timing and communicate with each other. This makes it possible to efficiently perform communication. Further, a period is provided in which both devices are in a state other than a reception state or a transmission state, whereby it is possible to reduce power consumption.
In an exemplary embodiment, the wireless system may execute an allowance period setting process for setting an allowance period for a connection between the first device and the second device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the allowance period, whether or not to execute the synchronous communication with the first device.
Based on the above, an allowance period is provided in a connection between the first device and the second device. Thus, for example, the second device is able not to perform synchronization communication with the first device. This makes it possible to reduce the power consumption of the second device as compared with the case where it is necessary to perform synchronization communication without exception.
Here, the “allowance period” may mean time or may mean the number of times it is not necessary to communicate with the second device.
In an exemplary embodiment, the first device may execute the allowance period setting process.
Based on the above, the first device can set the allowance period.
In an exemplary embodiment, the second device in the state of being connected to the first device may transmit a change request to change the allowance period.
Based on the above, the second device can request the first device to change the allowance period.
In an exemplary embodiment. The first device in the state of being connected to the second device repeatedly may transmit predetermined data to the second device at a predetermined time interval as the synchronous communication. The second device may return a response to the first device in accordance with the reception of the predetermined data transmitted from the first device at the predetermined time interval. In the allowance period setting process, the number of times of the response may be set as the allowance period, and if the number of times the second device does not return the response to the first device exceeds the number of times set in the allowance period setting process or reaches the number of times set in the allowance period setting process, the second device may return the response to the first device.
Based on the above, the second device is able not to return a response to the first device. This makes it possible to reduce the power consumption and also avoid the risk of terminating the connection with the first device.
In an exemplary embodiment, the second device may perform wireless communication with the third device in the state of being connected as a slave to the fourth device in the allowance period.
Based on the above, the device can communicate with the third device while maintaining the connection with the first device.
In an exemplary embodiment, the second device may execute a transmission process for wirelessly transmitting data by broadcast or multicast, and may execute a reception process for wirelessly receiving data transmitted by broadcast or multicast. The second device may repeatedly execute the transmission process and the reception process in the allowance period, thereby performing wireless communication with the third device in the state of being connected as a slave to the fourth device.
Based on the above, the second device can communicate with the third device in the allowance period and can communicate with the third device while maintaining the connection with the first device.
In an exemplary embodiment, the second device may establish a connection with the third device in the state of being connected as a slave to the fourth device in the allowance period, and in the state of being connected to the third device may perform wireless communication with the third device.
Based on the above, the second device can communicate with the third device in the allowance period and can connect to and communicate with the third device while maintaining the connection with the first device.
In an exemplary embodiment, the second device may perform wireless communication with the third device in the state of being connected as a slave to the fourth device at timing different from timing when the first device and the second device perform synchronous communication with each other.
Based on the above, the second device can communicate with the third device at timing other than timing for performing synchronous communication with the first device. For example, the second device can communicate with the third device while maintaining the connection with the first device.
In an exemplary embodiment, the first device and the second device may repeatedly perform synchronous communication with each other, and the fourth device and the third device may repeatedly perform synchronous communication with each other.
Based on the above, the first device and the second device can perform synchronous communication with each other, and the third device and the fourth device can perform synchronous communication with each other. This makes it possible to, for example, efficiently perform communication between the devices and also reduce power consumption.
In an exemplary embodiment, the wireless communication system may further execute an adjustment process for adjusting at least either one of timing of the synchronous communication between the first device and the second device and timing of the synchronous communication between the fourth device and the third device.
Based on the above, it is possible to adjust the timing of the synchronous communication between the first device and the second device and the timing of the synchronous communication between the fourth device and the third device.
In an exemplary embodiment, the second device may execute the adjustment process.
Based on the above, the second device can adjust the timing of the synchronous communication.
In an exemplary embodiment, in the adjustment process, the timing of the synchronous communication between the first device and the second device and the timing of the synchronous communication between the fourth device and the third device may be adjusted to be close to each other.
Based on the above, it is possible to adjust the timing of the synchronous communication between the first device and the second device and the timing of the synchronous communication between the fourth device and the third device to be close to each other. This makes it possible to efficiently perform communication between the second device and the third device. That is, the timing of the synchronous communication between the first device and the second device and the timing of the synchronous communication between the fourth device and the third device are matched, whereby it is possible to cause the period in which the second device does not perform synchronous communication with the first device to overlap the period in which the third device does not perform synchronous communication with the fourth device. In this overlapping period, the second device and the third device can communicate with each other.
In an exemplary embodiment, the wireless system may execute an allowance period setting process for setting an allowance period for a connection between the first device and the second device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the allowance period, whether or not to execute the synchronous communication with the first device. In the adjustment process, timing of at least either one of the synchronous communication between the first device and the second device and the synchronous communication between the third device and the fourth device may be adjusted so that the first device and the second device perform synchronous communication with each other in the allowance period.
Based on the above, for example, it is possible to adjust the timing of the synchronous communication while avoiding the risk of terminating the connection between the first device and the second device.
In an exemplary embodiment, the second device may execute the adjustment process. The third device may transmit information indicating the timing of the synchronous communication to be performed between the third device and the fourth device. Based on the information transmitted from the third device, the second device may adjust the timing of the synchronous communication to be performed between the second device and the first device.
Based on the above, the second device can receive, from the third device, information about the timing when the third device and the fourth device perform synchronization communication with each other. Thus, it is possible to adjust the timing of synchronous communication based on the information.
In an exemplary embodiment, in the state where the first device and the second device are connected together, the first device and the second device may repeatedly perform synchronous communication with each other. At timing when the first device and the second device perform synchronous communication with each other, the second device may perform wireless communication with the first device in priority to wireless communication between the second device and the third device.
Based on the above, the second device can preferentially perform communication with the first device. For example, the second device can communicate with the third device while communicating with the first device so that a connection with the first device is not terminated.
In an exemplary embodiment, the wireless system may execute an allowance period setting process for setting an allowance period for a connection between the first device and the second device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the allowance period, whether or not to execute the synchronous communication with the first device, and may execute a communication control process for controlling at least either one of the communication with the third device and the communication with the first device so that the first device and the second device perform synchronous communication with each other in the allowance period.
Based on the above, the second device can communicate with the third device while avoiding the risk of terminating the connection with the first device.
In an exemplary embodiment, the second device may execute a transmission process for wirelessly transmitting data by broadcast or multicast, and may execute a reception process for wirelessly receiving data transmitted by broadcast or multicast. Further, the second device in the state of being connected as a slave to the first device may repeatedly execute the transmission process and the reception process, thereby performing wireless communication with the third device in the state of being connected as a slave to the fourth device, without establishing a connection with the third device. Further, if timing of synchronous communication with the first device and timing of wireless communication with the third device overlap each other, the second device may preferentially perform the synchronous communication with the first device.
Based on the above, the second device transmits and receives data by broadcast, and thereby can communicate with the third device. At the timing for performing synchronous communication with the first device, the second device can preferentially perform communication with the first device. This enables the second device to, for example, communicate with the third device while communicating with the first device so that the connection with the first device is not terminated.
In an exemplary embodiment, the second device may establish a connection with the third device in the state of being connected as a slave to the fourth device, and in the state of being connected to the third device may perform wireless communication with the third device. If timing for performing synchronous communication with the first device and timing of wireless communication in the connection between the second device and the third device overlap each other, the second device may preferentially perform the communication with the first device.
Based on the above, the second device can establish a connection with and communicate with the third device. At the timing for performing synchronous communication with the first device, the second device can perform the communication with the first device in priority to the communication with the third device. This enables the second device to, for example, communicate with the third device while communicating the first device so that the connection with the first device is not terminated.
In an exemplary embodiment, the wireless system may execute a second allowance period setting process for setting a second allowance period for a connection between the second device and the third device. The second device and the third device in the state of being connected to each other may execute synchronous communication with each other. The third device in the state of being connected to the second device may execute a determination process for determining, based on the second allowance period, whether or not to execute synchronous communication with the second device. The second device may execute a communication control process for controlling at least either one of the communication with the third device and the communication with the first device so that the second device and the third device perform synchronous communication with each other in the second allowance period.
Based on the above, for example, the second device can control communication with the third device and communication with the first device so that the connection with the third device is not terminated.
In an exemplary embodiment, the second device may set a time interval of synchronous communication in the connection between the second device and the third device and may perform synchronous communication with the third device at the set time interval, and the second device may adjust the time interval of the synchronous communication with the third device, thereby preferentially performing communication with the first device.
Based on the above, for example, the second device lengthens the time intervals in synchronous communication with the third device, and thereby can communicate with the first device in the period in which the second device does not perform synchronous communication with the third device. Thus, the second device can preferentially perform the communication with the first device.
In an exemplary embodiment, the wireless system may execute a second allowance period setting process for setting a second allowance period for a connection between the second device and the third device, and may execute a third allowance period setting process for setting a third allowance period for a connection between the fourth device and the third device. The third device in the state of being connected to the second device may execute a determination process for determining, based on the second allowance period, whether or not to execute synchronous communication with the second device. The fourth device in the state of being connected to the third device may execute synchronous communication with the third device. The third device in the state of being connected to the fourth device may determine, based on the third allowance period, whether or not to execute synchronous communication with the fourth device. The third device may execute the synchronous communication with the fourth device in priority to the synchronous communication with the second device.
Based on the above, the second device and the third device are connected together, and a second allowance period is set for this connection. The third device and the fourth device are connected together, and a third allowance period is set for this connection. In the third allowance period, the third device executes synchronous communication with the fourth device and executes the synchronous communication with the fourth device in priority to the synchronous communication with the second device. This enables the third device to avoid the risk of terminating the connection with the fourth device.
In an exemplary embodiment, in accordance with a state of communication with the second device, the third device may transmit to the fourth device a change request to change the third allowance period.
Based on the above, the third device can cause the fourth device to change the third allowance period.
In an exemplary embodiment, the second device may execute an interval setting process for setting an interval of wireless communication. The second device establishes a connection with the third device in the state of being connected as a slave to the fourth device and then performs wireless communication between the second device and the third device at the interval set in the interval setting process.
Based on the above, the second device can communicate with the third device at a set interval.
In an exemplary embodiment, the wireless system may execute an allowance period setting process for setting an allowance period for a connection between the first device and the second device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the allowance period, whether or not to execute synchronous communication with the first device. In the interval setting process, based on the allowance period for the connection between the first device and the second device, the interval of wireless communication between the second device and the third device may be set.
Based on the above, the second device can set the interval of communication with the third device based on an allowance period in a connection with the first device.
In an exemplary embodiment, in the interval setting process by the second device, in accordance with a state of communication between the first device and the second device, a time interval of communication with the third device may be set.
Based on the above, the second device can communicate with the third device at a time interval corresponding to the state of communication between the first device and the second device.
In an exemplary embodiment, the wireless system may execute a second allowance period setting process for setting a second allowance period for a connection between the second device and the third device. The third device in the state of being connected to the second device may execute a determination process for determining, based on the second allowance period, whether or not to execute synchronous communication with the second device. In the second allowance period setting process, in accordance with a state of communication between the first device and the second device, the second allowance period may be set.
Based on the above, it is possible to set a second allowance period in accordance with the state of communication between the first device and the second device. For example, it is possible to lengthen or shorten an allowance period in a connection between the second device and the third device in accordance with the state of communication between the first device and the second device.
In an exemplary embodiment, the first device and the second device may perform synchronous communication with each other at a first time interval, and while being connected to the first device, the second device may establish a connection with the third device in the state of being connected as a slave to the fourth device and may perform synchronous communication with the third device at a second time interval different from the first time interval.
Based on the above, it is possible to differentiate the time interval of synchronous communication between the first device and the second device and the time interval of synchronous communication between the second device and the third device.
In an exemplary embodiment, the second device may set the second time interval to be shorter than the first time interval.
Based on the above, a second time interval is shorter than a first time interval. Thus, the second device can communicate with the third device more frequently than with the first device. Thus, the second device and the third device can exchange a large amount of data in a relatively short time.
In an exemplary embodiment, the wireless system may execute a first allowance period setting process for setting a first allowance period for a connection between the first device and the second device, and may execute a second allowance period setting process for setting a second allowance period for a connection between the second device and the third device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the first allowance period, whether or not to execute synchronous communication with the first device. The third device in the state of being connected to the second device may execute a determination process for determining, based on the second allowance period, whether or not to execute synchronous communication with the second device. In the second allowance period setting process, in accordance with at least either one of a state of the communication between the first device and the second device and the state of the communication between the second device and the third device, the second allowance period may be set to be shorter than the first allowance period.
Based on the above, it is possible to make a second allowance period in a connection between the second device and the third device shorter than a first allowance period in a connection between the first device and the second device. This enables the second device to reduce the risk of terminating the connection with the first device. For example, this configuration may be employed in a case where the second device exchanges data with the first device at a low frequency in a relatively long period while exchanging data with the third device at a high frequency in a relatively short period.
In an exemplary embodiment, the second device may set the second time interval to be longer than the first time interval.
Based on the above, a first time interval is shorter than a second time interval. Thus, the second device can communicate with the third device more frequently than with the first device. Thus, the first device and the second device can exchange relatively a large amount of data in a short time.
In an exemplary embodiment, the wireless system may execute a first allowance period setting process for setting a first allowance period for a connection between the first device and the second device, and may execute a second allowance period setting process for setting a second allowance period for a connection between the second device and the third device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the first allowance period, whether or not to execute synchronous communication with the first device. The third device in the state of being connected to the second device may execute a determination process for determining, based on the second allowance period, whether or not to execute synchronous communication with the second device. In the second allowance period setting process, the second allowance period may be set to be longer than the first allowance period.
Based on the above, it is possible to make a second allowance period in a connection between the second device and the third device longer than a first allowance period in a connection between the first device and the second device. This enables the second device to reduce the risk of terminating the connection with the third device. For example, this configuration may be employed in a case where the second device exchanges data with the third device at a low frequency in a relatively long period while exchanging data with the first device at a relatively high frequency.
In an exemplary embodiment, the second device, while being connected to the first device, may establish a connection with the third device in the state of being connected as a slave to the fourth device, and may give priority to the connection between the first device and the second device between over the connection between the second device and the third device.
Based on the above, the second device can connect to and communicate with the third device while giving priority to a connection with the first device.
In an exemplary embodiment, in accordance with a connection state between the first device and the second device, the second device may restrict communication between the second device and the third device.
Based on the above, in accordance with a connection state with the first device, the second device can restrict communication with the third device. For example, if there is a risk of terminating the connection with the first device, the second device can restrict communication with the third device.
In an exemplary embodiment, in a case where the connection between the first device and the second device is to be terminated if the connection between the second device and the third device is maintained, the second device may terminate the connection between the second device and the third device.
Based on the above, if there is a risk of terminating the connection with the first device, the second device can terminate a connection with the third device.
In an exemplary embodiment, the second device may execute a transmission process for wirelessly transmitting data, and may execute a reception process for wirelessly receiving data at timing different from the transmission of the data in the transmission process. The second device may repeatedly execute the transmission process and the reception process, and in the transmission process, data including timing information indicating timing of the transmission process and/or the reception process to be executed by the second device next time or later may be transmitted.
Based on the above, the second device can notify another device of the timing when the second device performs a transmission process and/or a reception process next time or later.
In an exemplary embodiment, in the transmission process by the second device, the data including the timing information may be transmitted by broadcast or multicast.
Based on the above, the second device can transmit the timing information to an unspecified device.
In an exemplary embodiment, in the transmission process by the second device, in accordance with reception of data transmitted from another device by broadcast or multicast, the data including the timing information may be transmitted.
Based on the above, in accordance with broadcast data from another device, the second device can transmit data including timing information.
In an exemplary embodiment, the third device may repeatedly execute a transmission process for wirelessly transmitting data and a reception process for wirelessly receiving data, and based on the timing information from the second device, may adjust timing for executing the transmission process and/or the reception process.
Based on the above, based on the timing information from the second device, the third device can adjust the timing for performing a transmission process and/or a reception process. This enables the second device and the third device to match the timing of the transmission process and the timing of the reception process.
In an exemplary embodiment, the wireless communication between the first device and the second device, the wireless communication between the fourth device and the third device, and the wireless communication between the second device and the third device may be all performed based on the same communication standard.
In an exemplary embodiment, each device may perform the wireless communication while switching a frequency of a radio wave.
In an exemplary embodiment, each device may perform the wireless communication while switching a plurality of predetermined different frequencies.
In an exemplary embodiment, the communication standard may be Bluetooth Low Energy.
In an exemplary embodiment, the wireless communication between the first device and the second device, the wireless communication between the fourth device and the third device, and the wireless communication between the second device and the third device may be all performed in the same predetermined frequency band.
In an exemplary embodiment, the frequency band may be the 2.4 GHz band.
In an exemplary embodiment, the search may be performed by switching between three channels.
In an exemplary embodiment, the second device in the state of being connected as a slave to the first device may execute a first process for wirelessly transmitting data by broadcast or multicast. The third device in the state of being connected as a slave to the fourth device may execute a second process for wirelessly receiving the data transmitted by broadcast or multicast in the first process executed by the second device.
Based on the above, the second device can transmit data by broadcast or multicast, and the third device can receive this data.
In an exemplary embodiment, the third device in the state of being connected as a slave to the fourth device may execute a third process for wirelessly transmitting data by broadcast or multicast. The second device in the state of being connected as a slave to the first device may execute a fourth process for wirelessly receiving the data transmitted by broadcast or multicast in the third process executed by the third device. The second device may alternately and repeatedly execute the first process and the fourth process. The third device may alternately and repeatedly execute the second process and the third process.
Based on the above, the third device in the state of being connected to the fourth device transmits and receives data by broadcast or multicast, and the second device in the state of being connected to the first device transmits and receives data by broadcast or multicast. This enables the third device and the second device connected as slaves to other devices to transmit and receive data to and from each other.
A sleep period in which neither the first process nor the fourth process is performed may be present between the first process and the fourth process, and a sleep period in which neither the second process nor the third process is performed may be present between the second process and the third process.
In an exemplary embodiment, the second device may execute a process of connecting to the third device having received the data transmitted in the first process, or a process of connecting to the third device having transmitted the data received in the fourth process. The third device may execute a process of connecting to the second device having transmitted the data received in the second process, or a process of connecting the second device having received the data transmitted in the third process.
Based on the above, the second device and the third device can connect to each other.
In an exemplary embodiment, the first device and the second device in the state of being connected to each other may repeatedly perform synchronous communication with each other. The second device may execute a communication control process for communicating wirelessly with the third device by avoiding timing when synchronous communication with the first device is executed.
Based on the above, the second device can repeatedly perform synchronization communication with the first device while communicating with the third device.
In an exemplary embodiment, the wireless system may execute an allowance period setting process for setting an allowance period regarding predetermined communication performed between the first device and the second device. The second device in the state of being connected to the first device may execute a determination process for determining, based on the allowance period, whether or not to execute predetermined communication with the first device, and may execute a communication control process for communicating wirelessly with the third device by avoiding timing when the predetermined communication to be executed according to the determination in the determination process is performed, so that the first device and the second device execute the predetermined communication to be executed according to the determination with each other.
Based on the above, the second device can communicate with the third device while avoiding the risk of terminating the connection with the first device.
Another configuration is a wireless system including a plurality of devices capable of performing wireless communication based on the Bluetooth Low Energy (BLE) standard, the wireless system including a first device, a second device, a fourth device, and a third device. The first device and the second device establish a connection between the first device and the second device such that the first device is a central and the second device is a peripheral, and perform wireless communication with each other based on the BLE standard. The fourth device and the third device establish a connection between the fourth device and the third device such that the fourth device is a central and the third device is a peripheral, and perform wireless communication with each other based on the BLE standard. The second device in a state where the connection between the first device and the second device is maintained, performs wireless communication based on the BLE standard with the third device in the state of being connected as a peripheral to the fourth device.
Another configuration may be a wireless device capable of performing wireless communication with a plurality of devices. The wireless device may execute: a connection establishment process for establishing a connection with a first device among the plurality of devices such that the first device is a master and the wireless device is a slave; and a communication process for, in the state of being connected as a slave to the first device, performing wireless communication with a third device in a state of being connected as a slave to a second device different from the first device. Further, another configuration may be a program to be executed by a processor of the wireless device.
Another configuration may be a program to be executed by a processor of the wireless device. Further, another configuration may be a communication method to be executed by the wireless system.
Another configuration may be a wireless system including a plurality of devices capable of performing wireless communication. The wireless system may include a first device and a second device. The first device and the second device establish a connection between the first device and the second device such that the first device is a master and the second device is a slave, and perform wireless communication with each other. The second device may execute: a transmission process for wirelessly transmitting data by broadcast or multicast; a reception process for receiving data wirelessly transmitted by broadcast or multicast; and an other device communication process for, in the state of being connected as a slave to the first device, repeatedly executing the transmission process and the reception process, thereby performing wireless communication with a third device different from the first device.
Another configuration may be a wireless device capable of performing wireless communication with a plurality of devices. The wireless device may execute: a connection establishment process for establishing a connection with a first device among the plurality of devices such that the first device is a master and the wireless device is a slave; a transmission process for wirelessly transmitting data by broadcast or multicast; a reception process for receiving data wirelessly transmitted by broadcast or multicast; and an other device communication process for, in the state of being connected as a slave to the first device, repeatedly executing the transmission process and the reception process, thereby performing wireless communication with a third device different from the first device.
Another configuration may be a wireless communications device comprising:
a wireless radio transceiver, and
a processor operatively coupled to the wireless radio transceiver, the processor configured to control the wireless communications device to:                establish a connection as a slave to a master device, and        in the state of being connected as a slave to the master device, wirelessly communicating with a further device connected as a slave to a further master device.        
Another configuration may be a wireless communications device comprising:
a wireless radio transceiver, and
a processor operatively coupled to the wireless radio transceiver, the processor configured to control the wireless communications device to:                establish a connection as a child to a parent device, and        in the state of being connected as a child to the master device, wirelessly communicating with a further device connected as a child to a further parent device.        
Another configuration may be a program to be executed by a processor of the wireless device. Further, another configuration may be a communication method to be executed by the wireless system.
According to the exemplary embodiment, a device connected as a slave can communicate with another device.
These and other objects, features, aspects and advantages of the exemplary embodiments will become more apparent from the following detailed description of the exemplary embodiments when taken in conjunction with the accompanying drawings.